Apparatus for measuring sizes of articles

• US 7,187,457 B2
• Filed: 02/19/2004
• Issued: 03/06/2007
• Est. Priority Date: 02/24/2003
• Status: Expired due to Fees

• Current Assignee: Shinko Denshi Co. Ltd. (Ishida Company Limited)
• Original Assignee: Shinko Denshi Co. Ltd. (Ishida Company Limited)
• Inventors: Kobayashi, Masaaki
• Primary Examiner(s): Lauchman; Layla G.
• Application Number:
  US10/780,871
• Publication Number:
  US 20040184042A1
• Time in Patent Office: 1,111 Days
• Field of Search: 356625-629, 356634-639, 356/601, 356/607, 356/608, 356/613, 209/586, 209/579, 250/559.12, 250/559.19
• US Class Current: 356/639
• CPC Class Codes: G01B 11/2433 for measuring outlines by shadow casting

Abstract

An apparatus for measuring sizes of articles including a light projecting device for projecting light toward an article placed on a stationary transparent plate from one side of the plate, a photo-sensor device arranged on the other side of the plate and having plural photo-detectors arranged in array in Y direction to receive light projected from the light projecting device and impinging upon the photo-sensor device without being interrupted by the article, a driving device for reciprocally moving the light projecting device and photo-sensor device relative to the article in X direction perpendicular to the Y direction, and a shifting device for shifting the photo-sensor device in the Y direction between first and second positions which are mutually separated by a half of a photo-detector array.

Claims

1. An apparatus for measuring sizes of articles comprising:

a light projecting device for projecting light toward an article from one side of an article;

a photo-sensor device arranged on the other side of the article and including a plurality of photo-detectors arranged in array in a first direction such that light projected from the light projecting device and impinging upon the photo-sensor device without being interrupted by the article is received by one or more photo-detectors;

a driving device for reciprocally moving the light projecting device and photo-sensor device relative to the article in a second direction perpendicular to the first direction;

a shifting device for shifting the photo-sensor device in the first direction into at least first and second positions which are mutually separated by a distance smaller than a pitch at which the photo-detectors are arranged in array;

a control device for controlling the driving device and shifting device such that when the light projecting device and photo-sensor device are moved by the driving device in a forward direction, the photo-sensor device is in the first position and when the light projecting device and photo-sensor device are moved by the driving device in a backward direction, the photo-sensor device is in the second position; and

a signal processing device for processing output signals generated from the photo-detectors under a control of a control signal supplied from the control device to measure size of the article with a resolution higher than the pitch at which the photo-detectors are arranged in array.

2. The apparatus according to claim 1, wherein the photo-detectors in the photo-sensor device are arranged into a single array with the pitch L and the photo-sensor device is shifted in the second direction over a distance of L/2.

3. The apparatus according to claim 1, wherein the photo-detectors in the photo-sensor device are arranged into n (n is integer equal to or larger than 2) rows with the pitch L and the n rows of photo-detectors are relatively shifted in the second direction by a distance L/n, and the photo-sensor device is shifted in the second direction over a distance of L/2n.

4. The apparatus according to claim 2, wherein the article is placed on a transparent plate and the light projecting device and the photo-sensor device are arranged on respective sides of the transparent plate.

5. The apparatus according to claim 4, wherein the transparent plate is arranged stationary and the light projecting device and photo-sensor device are arranged movably in the first direction.

6. The apparatus according to claim 5, wherein the light projecting device is provided on a lower horizontal portion of a frame and the photo-sensor device is provided on an upper horizontal portion of the frame, and the frame is arranged movably in the first direction.

7. The apparatus according to claim 1, wherein the light projecting device includes plural light emitting elements arranged in the second direction to project a substantially parallel light flux.

8. The apparatus according to claim 7, wherein the number of the light emitting elements is identical with that of the photo-detectors, and the light emitting elements are arranged in array to be corresponding to respective photo-detectors one by one.

9. The apparatus according to claim 8, wherein the array of the light emitting elements is shifted in the second direction together with the photo-sensor device.

10. The apparatus according to claim 3, wherein the article is placed on a transparent plate and the light projecting device and the photo-sensor device are arranged on respective sides of the transparent plate.

11. The apparatus according to claim 10, wherein the transparent plate is arranged stationary and the light projecting device and photo-sensor device are arranged movably in the first direction.

12. The apparatus according to claim 11, wherein the light projecting device is provided on a lower horizontal portion of a frame and the photo-sensor device is provided on an upper horizontal portion of the frame, and the frame is arranged movably in the first direction.